As a fish continues to run off line, the diameter of the line on the spool decreases, which, in turn, increases drag. Also, more line pulled through the water creates more pressure. When in this situation, slowly back off the drag as the fish runs, to alleviate the tension on your outfit. There will be enough drag from all the line in the water to keep the hook in a fish. Never tighten the drag if a fish is taking a lot of line. Drags should be checked before leaving the the dock and after each big catch.
— George Poveromo